刘乃征,朱培民,杜利明

• 1:中国地质大学(武汉)地球物理与空间信息学院
• 2:中国冶金地质总局山东正元地质勘查院
• 3:中国地质大学(武汉)高等研究院

摘要(Abstract)：

在重力反演中，传统的反演方法通常会生成平滑的反演结果，即不同的地质单元之间没有明显的边界。为了提高反演结果的空间分辨率和反演精度，采用模糊C均值聚类算法(fuzzy C-means,简称FCM)解决上述问题。但当异常体体积远小于围岩体积以及目标函数FCM聚类项权重系数选择不当时，该算法容易造成异常体反演结果均匀收缩，导致反演精度降低，甚至反演失败。反演失败的主要原因通常是因为异常体体积比围岩体积小很多。为此在反演的目标函数FCM聚类项中引入了缩放因子，用以平衡模型参数对每个聚类的隶属度，减小异常体体积远小于围岩体积的影响。通过建立缩放指数e_k与归一化的聚类中心与实际聚类中心间距离S_(normal)的简单正相关关系，使得缩放因子ρ_k随反演过程不断更新，从而显著降低了目标函数FCM聚类项权重系数的选择难度，避免了异常体反演结果均匀收缩的问题，增强了反演的稳定性。理论重力异常数据反演数值试验和实际数据反演表明，相比于此前的FCM方法，改进算法有更高的反演稳定性和反演精度。

关键词(KeyWords)： 三维重力反演;FCM聚类;缩放因子

Abstract:

Keywords:

基金项目(Foundation): 国家重点研发计划项目“城市地下空间开发地下全要素信息精准探测技术与装备”(2019YFC0605101)

作者(Author): 刘乃征,朱培民,杜利明

DOI: 10.19509/j.cnki.dzkq.tb20210606

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